This variety is reported to have sprung from a pit of a Mazzard tree and was introduced several years ago by Black & Son of Hightstown, New Jersey. The name, Mercer, after the county in New Jersey from which it was introduced, was given the cherry by H. E. Van Deman, then United States Pomologist. Tree vigorous, healthy, not always productive; branches long, grayish-brown, smooth, with a few small, inconspicuous lenticels. Leaves numerous, four and one-half inches long, two and one-fourth inches wide, folded upward, long-oval, leathery; upper surface dark green, smooth; lower surface light green, pubescent, grooved along the midrib; apex taper-pointed, base abrupt; margin coarsely and doubly serrate, glandular; petiole one and one-half inches long, tinged with dull red, thick, with from two to five very large, reniform, reddish glands, variable in position. Buds of medium size and length, conical, plump, free; leaf-scars rather prominent; season of bloom early; flowers one and one-fourth inches across, in scattering clusters in twos and threes; pedicels three-fourths inch long, glabrous; calyx-tube green or faintly tinged red, campanulate, glabrous; calyx-lobes greenish streaked with red along the edges, long, obtuse, glabrous within and without, reflexed; petals broad-oval, entire, slightly indented at the apex, tapering to short, blunt claws; filaments one-half inch long, shorter than the petals; pistil glabrous, shorter than the stamens. Fruit matures in mid-season; small, cordate to blunt-conic, compressed; cavity shallow, narrow, abrupt; suture an indistinct line; apex flattened or depressed; color black; dots small, numerous, obscure; stem slender, one and one-fourth inches long, adherent to the fruit; skin thin, rather tender; flesh reddish, with dark colored juice, tender, meaty, crisp, aromatic, mild flavored, sweet; fair to good in quality; stone free or semi-clinging, variable in size, ovate, flattened, blunt-pointed, with smooth surfaces, tinged with red. MEZEL _Prunus avium_ =1.= _Am. Pom. Soc. Cat._ 26. 1909. _Bigarreau Monstrueux._ =2.= _Lond. Hort. Soc. Cat._ 46. 1831. _Bigarreau of Mezel._ =3.= _Horticulturist_ =1=:475 fig., 476. 1846-47. =4.= Mortillet _Le Cerisier_ =2=:107 fig., 108. 1866. =5.= Downing _Fr. Trees Am._ 454. 1869. =6.= Leroy _Dict. Pom._ =5=:218 fig., 219. 1877. _Great Bigarreau._ =7.= _Horticulturist_ =6=:20 fig., 21. 1851. =8.= Downing _Fr. Trees Am._ 253. 1857. _Monstreuse de Mezel._ =9.= _Am. Pom. Soc. Cat._ 74. 1862. _Schwarze Knorpel von Mezel._ =10.= Mathieu _Nom. Pom._ 377. 1889.